CI: full rewrite - moved logic into ci.py and kept workflow scripts mostly dummy

.github/workflows/obsolete/sidestore-shared.yml

@@ -0,0 +1,24 @@
+name: SideStore Shared
+
+on:
+  workflow_call:
+    outputs:
+      short-commit: 
+        value: ${{ jobs.shared.outputs.short-commit }}
+
+jobs:
+  shared:
+    name: Shared Steps
+    strategy:
+      fail-fast: false
+    runs-on: 'macos-15'
+    steps:
+      - name: Set short commit hash
+        id: commit-id
+        run: |
+          # SHORT_COMMIT="${{ github.sha }}"
+          SHORT_COMMIT=${GITHUB_SHA:0:7}
+          echo "Short commit hash: $SHORT_COMMIT"
+          echo "SHORT_COMMIT=$SHORT_COMMIT" >> $GITHUB_OUTPUT
+    outputs:
+      short-commit: ${{ steps.commit-id.outputs.SHORT_COMMIT }}